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QJEEM22Ch684a: JEE Main 2022 Chemistry - Class 12 JEEM22Ch684a Solution: Which of the reaction is suitable for concentrating ore by…

Which of the reaction is suitable for concentrating ore by leaching process ?

A $2 \mathrm{Cu}_{2} \mathrm{~S}+3 \mathrm{O}_{2} \rightarrow 2 \mathrm{Cu}_{2} \mathrm{O}+2 \mathrm{SO}_{2}$
B $\mathrm{Fe}_{3} \mathrm{O}_{4}+\mathrm{CO} \rightarrow 3 \mathrm{FeO}+\mathrm{CO}_{2}$
C $\mathrm{Al}_{2} \mathrm{O}_{3}+2 \mathrm{NaOH}+3 \mathrm{H}_{2} \mathrm{O} \rightarrow 2 \mathrm{Na}\left[\mathrm{Al}(\mathrm{OH})_{4}\right]$
D $\mathrm{Al}_{2} \mathrm{O}_{3}+6 \mathrm{Mg} \rightarrow 6 \mathrm{MgO}+4 \mathrm{Al}$

Step-by-Step Verified Solution

Leaching involves the treatment of ore with a suitable reagent so as it make it soluble while impurities remain insoluble.

\mathrm{Al}_{2} \mathrm{O}_{3}+2 \mathrm{NaOH}+3 \mathrm{H}_{2} \mathrm{O} \rightarrow \underset{\text{Soluble complex}}{2 \mathrm{Na}\left[\mathrm{Al}(\mathrm{OH})_{4}\right]}